cmd/go: clarify that -coverpkg uses import paths

This change amends the long-form help output for 'go help build' and
'go help testflag' to specify that the '-coverpkg' flag operates
explicitly on import paths as well as package names. Import paths are
fundamental for precise specification of packages versus unqualified
package names, and the naming of the flag '-coverpkg' and its original
documentation leads a user to assume that it only operates on the
simple, unqualified package name form. The situation warrants
clarification.

Fixes #69653

Change-Id: Ifde6a974405ce1614e28898fc2b92ed5bad94e57
GitHub-Last-Rev: 466c662a70d13560f2fb7affb0d7d900889c7aa7
GitHub-Pull-Request: golang/go#69655
Reviewed-on: https://go-review.googlesource.com/c/go/+/616257
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index dcb2352beced7d7b5ae2130af5daa35205f30177..71bb838ae19e81b552ca55cb9bdd70a576d49303 100644 (file)
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -146,10 +146,11 @@
 //             Sets -cover.
 //     -coverpkg pattern1,pattern2,pattern3
 //             For a build that targets package 'main' (e.g. building a Go
-//             executable), apply coverage analysis to each package matching
-//             the patterns. The default is to apply coverage analysis to
-//             packages in the main Go module. See 'go help packages' for a
-//             description of package patterns.  Sets -cover.
+//             executable), apply coverage analysis to each package whose
+//             import path matches the patterns. The default is to apply
+//             coverage analysis to packages in the main Go module. See
+//             'go help packages' for a description of package patterns.
+//             Sets -cover.
 //     -v
 //             print the names of packages as they are compiled.
 //     -work
@@ -2953,6 +2954,12 @@
 // - "cmd" expands to the Go repository's commands and their
 // internal libraries.
 //
+// Package names match against fully-qualified import paths or patterns that
+// match against any number of import paths. For instance, "fmt" refers to the
+// standard library's package fmt, but "http" alone for package http would not
+// match the import path "net/http" from the standard library. Instead, the
+// complete import path "net/http" must be used.
+//
 // Import paths beginning with "cmd/" only match source code in
 // the Go repository.
 //
@@ -2982,7 +2989,10 @@
 // unique prefix that belongs to you. For example, paths used
 // internally at Google all begin with 'google', and paths
 // denoting remote repositories begin with the path to the code,
-// such as 'github.com/user/repo'.
+// such as 'github.com/user/repo'. Package patterns should include this prefix.
+// For instance, a package called 'http' residing under 'github.com/user/repo',
+// would be addressed with the fully-qualified pattern:
+// 'github.com/user/repo/http'.
 //
 // Packages in a program need not have unique package names,
 // but there are two reserved package names with special meaning.
@@ -3099,10 +3109,10 @@
 //         Sets -cover.
 //
 //     -coverpkg pattern1,pattern2,pattern3
-//         Apply coverage analysis in each test to packages matching the patterns.
-//         The default is for each test to analyze only the package being tested.
-//         See 'go help packages' for a description of package patterns.
-//         Sets -cover.
+//         Apply coverage analysis in each test to packages whose import paths
+//         match the patterns. The default is for each test to analyze only
+//         the package being tested. See 'go help packages' for a description
+//         of package patterns. Sets -cover.
 //
 //     -cpu 1,2,4
 //         Specify a list of GOMAXPROCS values for which the tests, benchmarks or

diff --git a/src/cmd/go/internal/help/helpdoc.go b/src/cmd/go/internal/help/helpdoc.go
index 9e3ef58e998717a1dfc08ec6c1f89c591b192eef..ec1567803fa32a7501f74ee87e4efa77406178aa 100644 (file)
--- a/src/cmd/go/internal/help/helpdoc.go
+++ b/src/cmd/go/internal/help/helpdoc.go
@@ -64,6 +64,12 @@ Go library.
 - "cmd" expands to the Go repository's commands and their
 internal libraries.
 
+Package names match against fully-qualified import paths or patterns that
+match against any number of import paths. For instance, "fmt" refers to the
+standard library's package fmt, but "http" alone for package http would not
+match the import path "net/http" from the standard library. Instead, the
+complete import path "net/http" must be used.
+
 Import paths beginning with "cmd/" only match source code in
 the Go repository.
 
@@ -93,7 +99,10 @@ By convention, this is arranged by starting each path with a
 unique prefix that belongs to you. For example, paths used
 internally at Google all begin with 'google', and paths
 denoting remote repositories begin with the path to the code,
-such as 'github.com/user/repo'.
+such as 'github.com/user/repo'. Package patterns should include this prefix.
+For instance, a package called 'http' residing under 'github.com/user/repo',
+would be addressed with the fully-qualified pattern:
+'github.com/user/repo/http'.
 
 Packages in a program need not have unique package names,
 but there are two reserved package names with special meaning.

diff --git a/src/cmd/go/internal/test/test.go b/src/cmd/go/internal/test/test.go
index 4bc9b5ea4cd1053202df4aa8cdcc617e38999040..58c54c99e050323da560bd3e902a79246dc68769 100644 (file)
--- a/src/cmd/go/internal/test/test.go
+++ b/src/cmd/go/internal/test/test.go
@@ -235,10 +235,10 @@ control the execution of any test:
            Sets -cover.
 
        -coverpkg pattern1,pattern2,pattern3
-           Apply coverage analysis in each test to packages matching the patterns.
-           The default is for each test to analyze only the package being tested.
-           See 'go help packages' for a description of package patterns.
-           Sets -cover.
+           Apply coverage analysis in each test to packages whose import paths
+           match the patterns. The default is for each test to analyze only
+           the package being tested. See 'go help packages' for a description
+           of package patterns. Sets -cover.
 
        -cpu 1,2,4
            Specify a list of GOMAXPROCS values for which the tests, benchmarks or

diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index 83caea9525fde18c85ebdb350f2a4513ddeafd4f..27246436e43f4a922d3d9e18e9ec428e88e8f649 100644 (file)
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -104,10 +104,11 @@ and test commands:
                Sets -cover.
        -coverpkg pattern1,pattern2,pattern3
                For a build that targets package 'main' (e.g. building a Go
-               executable), apply coverage analysis to each package matching
-               the patterns. The default is to apply coverage analysis to
-               packages in the main Go module. See 'go help packages' for a
-               description of package patterns.  Sets -cover.
+               executable), apply coverage analysis to each package whose
+               import path matches the patterns. The default is to apply
+               coverage analysis to packages in the main Go module. See
+               'go help packages' for a description of package patterns.
+               Sets -cover.
        -v
                print the names of packages as they are compiled.
        -work